The present invention relates to pressure sensors. More particularly, the present invention relates to a pressure sensor body designed to permit rigid mounting of the pressure sensor to a larger assembly.
Differential pressure sensors or differential pressure transducers are known in the art. The differential pressure sensors include at least first and second pressure inlet ports. The first (low) pressure inlet port may be attached to a low pressure inlet line and the second (high) pressure port may be attached to a higher pressure inlet line. The differential pressure transmitter returns an electrical signal indicative of the difference in pressure between the higher pressure line and the low pressure line. The differential pressure transmitter is intended to measure a difference in pressure with substantially no flow between the pressure lines. The transmitter may include a single diaphragm or other sensor element affected by the low pressure and the higher pressure on both opposing sides, or it may include two separate pressure sensors with the measured pressure low pressure electrically compared against the measured high pressure.
Such pressure sensors are most commonly supplied on a stand-alone basis. Installation in the field may require two or more individuals: an electrician to run the electrical lines and a plumber or pipe-fitter to run the fluid lines. Additionally, the plumber or pipe-fitter may install isolation valves on the ends of the low pressure line and the high pressure line to facilitate removal or replacement of the pressure sensor(s) or transducer(s). The isolation valves can be closed to close off or xe2x80x9cisolatexe2x80x9d the high and low pressure lines from the pressure sensor elements.
Differential pressure sensors assemblies or differential pressure transmitter assemblies are known in the art. These assemblies incorporate both the pressure sensor assembly and the isolation valve assembly as a single manufactured product, and thus require less field installation time. In particular, the connections made between the isolation valves and the pressure sensor(s) may be made as a manufacturing step for the assembly rather than in the field.
Known differential pressure transmitters may be assembled from relatively low cost components, but assembly and/or installation time and costs may be significant. Improvements are needed to reduce the cost and increase the functionality both in the manufacture and in the installation of such pressure transmitters.
The present invention is a sensor primarily including a sensing element and a sensor housing. The sensing element measures at least one fluid parameter, such as pressure. The sensor housing provides a sealed chamber in fluid communication with the sensing element. The sensor housing has a smooth surface for mating with the sensing element. The sensor housing also has a threaded interior surface opposite the sensing element for rotational attachment to a tubing or piping system. The sensor housing also has a flange defining two planar surfaces normal to the central axis of the interior chamber. One of the planar surfaces has threaded bore holes extending less than the full width of the flange, allowing for fixable attachment of the flange to a structure. In one aspect, a body extends outward from the flange, and provides the threaded interior chamber. The body has an exterior surface with at least one flat normal to the planar surfaces of the flange. The flats are positioned adjacent to each bore hole to allow the head of the screw to mate with the flange surface. In another embodiment, a neck extends from one side of the flange defining the interior chamber, and the sensing element is attached to a smooth surface of the neck.